Work supporting table



May 5, 1936. c. H. HowLAND-sHEARMAN WORK SUPPORTING TABLE 8"Sheets-Sheet 1 Filed July 27, 1954 NNN WNW DNN www,

` ATTORNEY May 5, 1936-l y c, H. HowLAND-sHEARMAN WORK SUPPORTING TABLE Filed July 27, 1934 8 Sheets-Sheet 2 a \\\\\a% Lm M M x1 H n mw) m maf o E W U w. A IM E um W N mm.) Y NM,\ r P irk E w.. \w\ R m. N NN P-- 51 mw N .n

May 5, 1936- c H. HowLAND-sHl-:ARMAN WORK SUPPORTING TABLE 8 Sheets-Shee't 3 Filed July 27, 1934 mm uw ATTORNEY May 5,-1936- c. H. HowLAND-sHr-:ARMAN 2,039,843 l wonx SUPPORTING TABLE Fuga July 27, 1934 8 s .xeigl-sheet 4 J. 0325 e" Q lv v 33 40 cimzzz am mama/v 43N BY ATTORNEY May 5, 1936- c, H. HowLAND-sHx-:ARMAN v 2,039,843

WORK SUPPORTING TABLE Filed July 27, 1934 8 Sheets-Shelf(l 5 ATTORNEY May 5, 1936- c. H. HowLAND-sHEARMAN 2,039,843

WORK SUPPORTING TABLE Filed July 27, 1934 8 Sheets-Sheet 6 i mv INVENTOR CHM/E5 All/@WMM-HEHRMYN ATTO R N EY May 5, 1936. c. H. HowLAND-sHEARMAN 2,039,843'

WORK SUPPORTING TABLE' Filed July 27, 1934 8 Sheets-Sheet 7 ATTORNEY C. H. HOWLAND-SHEARMAN woRK SUPORTING TABLE Filed July 27, 1934 8 Sheets-Sheet 8 INVENTOR CHHRLEH fHahz/z/w'mfmlv ATTORNEY May 5, 1936.

Cal

Patented May 5, 1936 UNITED STATES PATENT ()FFICE WORK SUPPORTING TABLE charles n. nowlana-shwm,`namden, com..

Application July 27, 1834, Serial* No..737,157

zo claims. (o1. 1er-ss) This invention relates to work supporting tables for machine tools and devices of a similar nature. It has for its purpose the provision of a vertically pulsating table applicable to a variety of structure but particularly suitable for use in the Kinetor or tractor lever machine fully set forth in my co-pendng applicationSerial No. 737,160, led July 27, 1934 and hereinafter described in iis relation to the present invention.

A further purpose is the provision of means to time the pulsation of the table with respect to the operating functions of the machine.

As a still further object, the invention provides accurate means to controland adjust the amplitude of pulsation of the table and the force applied thereby independently of each other.

Figure 1 is a side elevation of a machine tool embodying the invention.

Figure 2 is a vertical sectional view of the table structure in its lower or retracted position.

Figure 3 is asimilar view of the same at the completion of its upward pulsation.

Figure 4 is a transverse section of the table structure.

Figure 5 is a fragmental detail view of the means of adjusting the vertical table guide bearings. l v

Figure 6 is a horizontal sectional' view of the vertical wedge and related parts.

Figure 7 shows the means' of adjusting the initial table position.

Figure 8 is a side view partly in section ofv the spring motor power storing and tripping,` means in automatically tripped position.

Figure 9 is a vertical cross section vof the spring motor and its adjusting means.

Figure 10 is a horizontal cross section of thel spring motor cylinder, lspring backing nut and adjusting sleeve.

Figure 1l is a view similar to Figure 8 but showing the mechanism cocked and at the point of tripping.

Figure 12 is an enlarged detail view of the automatic tripping device showing the shifter block in semi-automatic setting.

Figure 13 is a detail top view of the wedge shown in Figure l2. Y l

Figure 14 is a left side elevation of the same.

Figures l5 and 16 are views of the cushioning dashpot.

Figure 1'? is a detail view of a part of the automatic and semi-automatic shifting linkage.

Referring to Figures l, 2, 3, and 4, the stationary'base II carries a pair of side plates of which the rear appears in this section and is indicated by the numeral I2. The plate I2 and its companion plate I3 (Figure 4) are fastened to the base II by means of bolts I4 and form therewith the stationary supporting frame of the machine.

The table supporting portion I5 of b ase II is 5 provided with horizontal shoes I6 forming ways for a wedge I1 slidable thereon. A work table I8, guided vertically on stationary rails I3 and 28 in a manner hereinafter described, is providedwith lower shoes 2|. bearing on the upper inclined sur- 10 face 22 of the wedge I'l. A bolster 23, bolted to the table I8, is adapted to receive die or rest plate which may be of any desired type such as that. shown having a main plate 24 and an inserted work portion 25.

It will be noted that bolster 23, table I8, wedge I1 and base I I are formed with central openings 26, 21, 28, and 29 respectively forming a chamber in the table structure. An ejector rod 30, which may be constructed with a detachable upper portion 3I carrying a shoe 32, is vertically slidable in a stationary sleeve 33 and is adapted to be reciprocated therein by a pedal lever 34 as shown more fully in Figure 4. The purpose of ejector rod 30 is to facilitate the removal of the die or rest plate parts for changes or repairs.

A horizontal rod 35 is fastened in any suitable manner such as the screw thread 38 to the wedge I1. A worm thread 31 is formed on the rod 35 and carries an internally threaded cylindrical member 38 slidable in a stationary guide 38.

A vertical wedge 40 has inclined rear surfaces 4I slidable on a stationary backing guide 42. 'Ihe guide 42 is formed with side portions 43 and 44, as shown in Figure 6, embracing the sides of an extension 45 of the wedge 40 in dove-tail relation. The wedge 48 is also provided with dove-tail side portions 46 and 41, Figure 6, embracing the sides of a forward shoe 48.which bears in slidable re- 4 lation against the vertical forward face 49 of wedge 40. The shoe 48 is rotatably retained on a hub 50 of the cylindrical member 38 by a threaded collar 5I. A screw key 52 locks the threads of the collar 5I and hub 58.

A bevel gear 53 is formed on or fastened to the cylindrical member 38. A seco-nd bevel gear 53a, Figure 7, fastened to a shaft 53h journalled in the side plate I3 and having an'exterior hand wheel 53e, is adapted to mesh with the gear 53 5 when the latter is in retracted or right hand position.

A toggle arm 54 is articulated to the wedge 40 by means of a pin 55. A lower toggle arm 56, articulatedvto arm 54 by a pin 5l, is fastened at u pin 58 journalled in l bell crank 62. Referring to Figure 8, the lever 64 carries a pin 65 which is connected by a short link 66 to a second pin 61 supported in a plunger 68 slidable vertically in a stationary cylinder 69 built integrally with or secured to the base I I. A nut 10 is adapted to be screwed up or down in the lower threaded portion 1| of cylinder 69. The nut 10 is formed with internal ilats 12, Figure 9, slidable longitudinally on corresponding flats 13 on a sleeve 14. Abevel gear 15 is secured to the lower end of the sleeve 14 by means of screw keys 16. A stationary nut 10a retains the sleeve 14 in the cylinder 69. rI'he gear 15 meshes with a second gear 11, Figure 10, mount# ed on a horizontal shaft 11a extending through the side of the base I| and carrying an external hand wheel 18. A rod 19, guided in the sleeve 14, is fastened at the top to the plunger 68 and terminates at the bottom in an eye portion 80.

A helical compression spring 8|, surrounding the rod 19, is disposed between the piston 68 and a thrust ring 82 carried on the top of sleeve 14. A second compression spring 83 of larger diameter than 8| but shorter length is supported by a thrust bearing 84 on the top of nut 10. A third spring 85, of diameter intermediate springs 8| and 83 but shorter than either is also supported by the thrust bearing 84, which may be of a roller type.

Springs 83 and 85 are preferably wound of wire having a cross section in the shape of a keystone, for reasons hereinafter explained. Disposed between the springs 83 and'85 andthe thrust bearing 84 is an indicator plate 86 having a iinger 31l extending through a slot 88, Figure 1, in the cylinder 69 and having indicating marks 89 adapted to register with graduation 90 on an external scale 9|. A short link 92 connects the eye portion with a walking,beam 93 by means of pins 94 and 95. The walking beam 93 is fulcrumed on a stationary cross shaft 96 supported in the base |I. The right arm 91 of the beam 93 is articulated on pin 98 which is secured in a radius yoke 99. A stationary cross pin |00, suitably secured to the base rotatably supports a beam I 0| hereinafter referred to as the micrometer beam, having downwardly extending side walls |02 and |03. 'I'he free end of beam |0I comprises a hollow block |04 in which is horizontally trunnioned a sleeve |05 carrying a micrometer screw |06 which is rotatable therein and axially restrained by pinned collars |01 and |08. Ihe screw |06 carries an adjusting hand wheel |06a which projects through the end of thebase as shown in Figure l. An internally threaded nut |09 on screw |06 carries side pins ||0 which are journalled in the top of the yoke 99. It will be understood that the yoke 99 spans the walls |02 and |03 of the beam |0I.

'I'he pin 98 projects through a curved slot |12 in the base I|, Figure 1, and carries a segmental dial |13 having graduations |14 adapted to register with a stationary pointer |15 when the parts are in the position shown in Figure 8. Rotatably mounted on the side pins I0 are segments I I I slidable in slots I I2 in the walls |02 and |033 The slots I I 2 are cut on a radius struck from the pin 98 when the parts are in the position shown in Figure 8.

A pin I |3, located in the longitudinal center of the beam IOI, carries a short link I I 4 which yis pivoted by means of a pin I|5 to a release plunger I I6. 'I'he release plunger I I 6 is vertically slidable in a stationary guide ||1. A stop pad |20 of rawhide or other suitable material is provided on the stationary frame I I under the plunger II6. A lift plunger'l 2 I, vertically slidable in the release plunger I|6, is secured to a vertical rod |22. 'I'he rod |22 is pivotally joined at |23 to an eccentric strap |24 cooperative with an eccentric |25 on a power shaft I 26 of the machine. 'Ihe lift plunger |2| has a lateral notch |21 adapted to receive the end of a latch |28 guided by upper and lower rollers |29 and |30 rotatably mounted in the release plunger II6. A compression spring |3| urges the latch |28 into the notch |21.

A manual release block |32, slldably dovetailed in the top of stationary guide |I1., has'a plunger |33 urged downward by a spring |34 and adapted to engage a notch |35 in the latch |28. A collar |36 on the top of plunger |33 limits its downward motion. A cross pin |31 in the end of block |32 engages a slot |38 in a lever |39 secured to a cross shaft |40 which is journalled in the side plates |2 and I3 of the machine.

Rockably mounted on a second cross shaft |4|,

journalled in the base II, is a lever |42 shown in lin the extended portion |41 slldably engages a groove |5| in the wedge |49.

A block |52 is slldably dovetailed to the bottom of the wedge |49 as shown in Figure 14. A screw |53, rotatable in a bushing |54 screwed into the bottom of lever |42 and retained therein by a col-` lar |55, is threaded into the block I 52 and has an exterior adjusting head |56. By turning the screw |53 the block |52 and wedge |49 may be moved up or down, the dovetail joint between the two permitting the wedge to move left or right as it slides along the inclined inner surface |48 of the'lever |42.

A shifter block |51 is slldably dovetailed to the right hand surface or front of the key |49, and is connected through a link |58 and pins- |59 and |60 with a short lever |6| fastened to the second cross shaft I4I. A second short lever |62, fasf tened to the shaft I4| behind the parts already 4described and shown in perspective in Figure 17, carries a pin |63 engaging a slot |64 in a lever |65 rockably mounted on a stationary pin |66'. 'Ihe upper end of lever |65 is connected by a link |61 and pins |68 and |69 with a lever |10 fastened to a rocking shaft I1I journalled in the stationaiy frame of the machine. A pull rod II8, articulate@ to lever |10 by pin I I9, is pivotally joined to a lever The lever |42, Figure 14, has upper and lowerv horizontal slideways I 82 and |83 between which is slidablyrdispcsed a trip block 84 having an extension |85 adapted to engage the shift block |51. The shift block |51 has a cut away portion |86 a pin 244 secured t0,-

l tension |90 of the micrometer beam |0 Referring to Figure 1, an exterior levery |9| is fastened to the cross shaft |40, and is pivotally connected at |92 to a horizontal link |93 which in turn is pivoted to a spud |94 screwed into a cylinder |95. A piston |96, slidable in cylinder |95, has a reduced piston rod |91 extending slidably through the head |98 of Vcylinder |95. The rod |91 is threaded into a clevis |99 which is pivoted at 200 to the upwardly extending arm 20| of a bell crank 202 rockably fastened to the base by means of a stationary pin 203. The horizontal arm 204 of the bell crank 202 terminates in a pedal l205.

A pull rod 206, swinging lever 201 and second pull rod 208 'connect the upper end of arm 20| with a lever 209 adapted to actuate the trip mechanism (not shown) of a clutch 20911. of any suitable type, preferably that shown and fully described in co-pending application rSerial No. '137,-

155, filed July 27, 1934. Retracting springs 2|0 and 2| connected tothe base ||.and side plate I3 respectively, urge the arm 20| and link |93 to the right. A link 2|2, pivoted at 2|3 tothe micrometer beam ||,4 is articulatedat 2|4 to a lever 2|5 rockably mounted on a pin 2|6 secured in the base The outwardly extending arm 2 I1 of lever 2|5 is connected by a link 2|8 to the wrist pin 2|9 of a piston 220 slidable vertically in a dash pot cylinder 22| secured to the base as shown in Figures 15 and 16.

Vent holes 2 22 are provided near the top of the cylinder 22|, and a longitudinal groove 223 inthe bore of 22| leads to a vent port 224 containing a tapered valve 225 having a shank 226 adjustably threaded through a stationary yoke 221. An adjusting handle 228 is provided on the end of shank The numeral 229, Figure 1,l indicates a clamping member attached to the working head 230 of the machine. The machine may be actuated 'by the power shaft |26 through any suitable linkage illustrated by a crank pin 23|, connecting rod 232 and lever 233. The shaft |26 may be driven by a motor 234 through aworm 235 and worm gear 236. The numeral 231 indicates a work piece supported by the table 23.

The operation of the device is as follows, assuming the parts to be positioned for automatic tripping as illustrated in Figures 8 and 11. In Figure 8 the springs 8|, B3 and 85 have expanded upward, forcing upward the plunger 68 and rocking the bell crank 62 counterclockwise and bringing the toggle levers 54 and 56 to the co-linear position shown in Figure 3. The vertical wedge 40 is thus thrust to its upper position, wedging the shoe 48 and cylindrical member 38 to the left, the member 38 sliding in the guide 39. Member 3 8 has carried with it the threaded rod 35, which i has thrust the wedge |1 to the left and thereby raised the table IB to its upper position guided by the vertical rails |9 and 20.

The release plunger |6, being connected through the link |4, micrometer beam |0|, yoke 99, lever 93 and link 92 with the rod 19 as previously described, is drawn to its lowest position as shown in Figure 8, the pad |20v acting as a stop for ||6 and therebydetermining the described position of the parts. The eccentric |25 on power shaft |26 having revolved to bottom dead center, Figure 8, the lift plunger |2| had.r descended inside the release plunger ||6 until the latch |28 has been snapped into the lateral notch |21 by the spring |3|. The movement of latch |28, acting through the rod |46, swings the lever |42 clockwise.

The eccentric |25 now revolves past bottom dead center and Ymoves upward, drawing upward 93, drawing the rod 19 and plunger 68 down-v ward. The bell crank 62 is thus swung clockwise, pulling the link 59 to the left and moving the toggle levers 54 and 56 to the angular position shown in Figure 2.

The toggle lever 56 being anchored at 58, the entire vertical or versed sine motion 'caused' by drawing out. the toggle acts to. draw the vertical wedge 40 downward. The wedge '40, as previously noted, is slidably dovetailed to both the stationary backing guide 42 and the shoe 48. When, therefore, the wedge 40 moves downward it draws the shoe 48, threaded collar cylindrical member 38 and rod 35 to the right, withdrawing thev sliding the trip block |84 toward the shifter block |51. As the plunger |-|,6 nears the top of its stroke the trip block |84 engages the shifter block and moves the latter'to the left, causing the lever |42 to swing also to the left. The pin |44 and rod |46 are pulled to the left, withdrawingthe latch'l28 from the lateral notch |21 as shown in Figure 11. The entire linkage compressing the springs 8|, 83, and 8 5 is thereby freed from the lift plunger |2|. The springs immediately expand, suddenly returning the -parts to the positions shown in Figures 3 and 8, except the eccentric |25, lift plunger |22 and their interconnections. The table |8 is thus given a rapid cated through the link 2 |2 to the lever 2| 5, rocking the outer arm of 2|5 upward and thereby raising the dash-pot piston 220, Figures 15 and 16. The air trapped in the dash-pot cylinder 22| above the piston 220 is forced out through the small holes 222 and the port 224,.the resistance to its exit giving a cushioning effect as the release plunger 6 lapproaches the stop pad |20.

The degree of cushioning effect may be varied by adjusting the restriction of port 224 by means of the tapered' valve 225.

From the foregoing description it is evident that the complete pulsating cycle of the table consists of a relatively slow downward or retracting movement followed by a sudden upward movement. Due to thelong stroke of the spring actuated plunger 68 and the compounded speed reduction of the toggle levers 54 and 56 land the wedges 40 and l1, the total rise of the tableis relatively small. The effective force of the powerful springs 8|, 83 and 85 is therefore multiplied many times and notwithstandingl the inertia o'f the parts the upward stroke of the table is practically instantaneous, subject only to the adjustable cushioning effect of the dash-pot 22|.

idling lor retracting stroke, Figure 1, the eccentric is generally set to reach top dead center at the commencement of the working ystroke.

'I'he timing of the withdrawal of atch |28 from the notch |21 in relation to the stroke of the plunger |2| and consequently to the working function of the machine is determined by the engagement of the trip block |84 with the shifter block |51 as previously described. By means of the screw |53, Figure 12, the wedge |49 may be adjusted upward or downward, thus moving the shifter block |51 to the right or left, causing an earlier or later engagement between the blocks |34 and |51. By this means an accurate and. delicate adjustment lof the tripping and consequent upward table pulsation is provided.

To vary the amplitude of the table pulsation,` the machine is stopped with the parts in the pol sition shown in Figure 8. If it is desired to shorten the'stroke, the micrometer screw |06 is operated by means of the hand wheel |06a, Figure 1,-to move the nut to the left. The slots ||2 being cut on a radius'swing about the center of the pin 98- in the position shown in Figure 8,

the position of 98 is not altered, but the segments |09 and pins ||0 are moved near the fulcrum |00 of the beam |0|. Consequently, when the beam I0| is raised by the action of the lift plunger |2 the link 99 imparts a shorter motion to the lever By this means the table is given a shorter stroke without alteration in its upper position.

Similarly, by moving the nut |||to the right the stroke may be lengthened.

The external dial |13, which registers with' the pointer |15, Figure 1, when the parts are as shown in Figure 8, swings with the link 99. The 4 graduations |1 4 are calibrated as increments of table movement. Consequently the table stroke and adjustments thereof may be read directly on the external dial |13. As the adjustment takes place at a point inthe linkage Where the movement oi' the parts is very 'large in relation to the corresponding table movement, the setting of thev latter is rendered very fine and accurate.

The position of the table I8 may -be adjusted as follows:

With the table in retracted position, as shown in Figure 2, the bevel gear 53 is adapted to mesh with the second bevel gear 53a when the latter is moved inward manually as shown in Figure '7'. By turning the hand wheel 53o the member 38 is revolved on the thread 31 thus moving the rod 35 longitudinally. The wedge I1 is thus shifted to lower or raisey the table I8. A spring 245 is provided to slide the shaft 53h outward and it, the hand thereby'hold the gear 53a out of meshing position with gear 53 except when the wheel 53o is pressed inward to make an adjustment. l

To Aincrease the force delivered bythe springs 48|, 83 and 85,-and consequently the upward force imparted to the table and work vmaterial above wheel 18, Figure 9, is revolved, causing the gear 11 to revolve the mating gear 15 and with it the sleeve 14. .The nut 10, being rotatively locked to sleeve `'I4 by the flats 12 and 13, Figure 10. is screwed upward in the threads 1| of cylinder 69, thus compressing the springs 8|,:83, and 85 against the plunger 68. The initial compression thus being increased, the springs after further compression by the lowering of the plunger 68 are adapted to raise the table |2 with increased force when the release apparatus is tripped.

Figure 9 shows the nut 10 in its lowest position. As previously noted, the springs 8|, 83 and 85 mayhave different free lengths,'so that with the nut at lowest position only the spring 8| normally bears against the plunger 68, the other springs being picked up successively as the nut is adjustedupward. This arrangement allows a greater range of adjustments than could be obtained if all springs were employed throughout the entire range. c

'I'he scale 9| is calibrated to read directly in upward force exerted through the table by a given combination and setting of springs.

The use of keystone wire in springs 83 and 85 promotes uniformity `of graduation on the scale 9|, as this type of spring when compressed gives anv increase in -pressure directly proportional to the linear decrease in length.

The operation of the device as thus far described has dealt with fully automatic action of the machine tool, the shaft |26 revolving continuously. With some classes of work it may be necessary to operate the machine intermittently, as for instance when work must be placed on the table and located by hand. For this purpose v and lever |6|, Figure 12. 'Ihe motion of'. |6| is transmitted through the link |58 to the shifter block |51 which is moved upward to the position shown in Figure 12. When the trip block |84 is now moved to the left by the upward motion of beam 0|, the extension |85, instead of encountering the shifter block |51, enters the clearance cut-out or notch |86 and hence does not trip the latch |28.

Assuming the machine to'have been (stopped by disengagement of the clutch 209a with the working' parts about to start the work stroke, that is with the eccentric |25 at or near topdead center, the spring motor has been cocked by theA completed, to trip the table pulsating mechanism f the pedal 205 is depressed as shown in Figure 1. The lever 202 swings to the left, acting through the rod |91,. piston |96, cylinder |95, spud |94 and link |93 to rock the lever |9|, shaft |40 and lever |39 clockwise. The lever |39 draws the block 32 to the left and the plunger |32 in notch |35 withdraws the latch |28 from the notch |21 to trip the spring motor. 'I'he table performs its upward pulsation. At the same time the lever 20|, Figure 1, may act through the rod 206, lever 201, rod 208 and lever 209 to trip the clutch 209a,

The plunger |33 of the manual release block 1 thus starting the machine on its working stroke.

spring motor cocked, as the` plunger |33 .can

engage the notch 135 in the latch |28 only when the release plunger I I6 is at or near the top of its stroke.

To illustrate a use of the functions of the pulsating table, it may be assumed that a work piece 231 is to be pressed upward against the clamping member 229 of the Kinetor, Figure 1, with a force previously determined as required by the work to be done on the material. It having also been determined from the nature of the material, possible thickness of scale or surface irregularities, and initial clearance between the work and clamping member 229, that a certain upward motion of the table is required to give proper clamping, the length of upward pulsation is set by means of the micrometer screw |06 and dial |13. The spring'motor is next adjusted to give t e desired force as previously described by means of hand wheel 18.

The work piece having been placed in position, the device isl tripped. The table pulsates upward pressing the work rmly between the rest plate 24-25, Figure 2, and the clamping member 229 and holding it thus while the required work is performed on it. The machine tool having performed its work, the table I8 is lowered as previously described, allowing the work piece 231 to be removed and replaced by a new piece.

The wide independent adjustments of the pressure and amplitude of pulsation allow the device to be set for a wide range of work, both heavy and light, and the neness of the adjustments make it suitable for use where extreme delicacy and accuracy are required. In some cases it may be desired to bring the work to full clamped condition before the toggle levers 5d and 56 are entirely alined, which purpose may be accomplished by a slight increase of the-setting for amplitude.

The low angles of the wedges l1 and Ml, together with the fact that the toggle 56--56 when at or near alinement approximate a rigid column, prevent any downward yielding of the tafble i8 under working pressure which may be applied to the piece 231i.

The forward pulsation of the heavy wedge l1 against the lower incline face of the table It, especially when large pulsating forces are being employed, imparts a horizontal component or throb to the table I8. These horizontal pressure pulsations are resisted by the vertical guide rails i9 and 29, and in time wear will result. To take up this wear and prevent looseness and loss of proper alinement the table i8 is equipped with wedge-shaped shoes 246 and 241, Figure 5, engaging each rail. A yoke 248 spanning the rail is adjustable upward and downward by means of nuts 269 and 251i on a stud fastened in the table it. Similar studs 252 and 253 pass- I to those skilled in the art, that the inventionv involves a result hitherto unobtained, namely, a quick table pulsation of separately adjustable predetermined amplitude and force, differing both in nature and function from the ordinary working, feeding or locating movements employed on planers, milling machines and similar tools.

While the invention is presented in preferred form as reduced to practice, it is not limited to the exact structure shown, as various modifications can be made without departing from the scope of the appended claims.

What is claimed is: 1. In combination working pressure applying means, amachine table having a work supporting face, means to pulsate said table perpendicularly to said face, to apply a predetermined pressure to a material supported on said table previous to the operation of said working pressure applying means, and means for holding lsaid table in ilxed position to permit said pressure applying means to perform work on said material.

2. In a machine tool in combination working pressure applying means, a power shaft, a horizontal work supporting table, means controllable by said power shaft to pulsate said table vertically, to apply a predetermined pressure to a material supported on said table previous to the operation of said working pressure applying means, and means for holding said table in xed position to permit said pressure applying means to perform work on said material.

3. In a machine tool in combination a power shaft, a work supporting table, and means to pulsate said table comprising means operable by said shaft to store energy, means operable by i said shaft to release said energy, and means to operatively apply said energy to said table.

4. In a machine tool in combination a power shaft, a work supporting table, and means to pulsate said table comprising means operable by said shaft to store energy, means operable by said shaft to release said energy in timed relation to the operation of said storing means, and {means to operatively apply `said energy to said able.

5. In a machine'tool in combination a power shaft, a work supporting table, and means to pulsate said 'table comprising means operable by said shaft to store energy, manually operable means to release said energy, and means to operatively apply said energy to said table.

6. In a machine tool in combination a power shaft, a work supporting table, and means to pulsate said table comprising means operable by said shaft to store energy, means operable by said shaft to vrelease said energy, manually operable means to release said energy, and means to operatively apply said energy to said table.

7. In a machine tool in combination a power shaft, a work supporting table, and means to pulsate said table comprising means operable by said shaft to store energy, means operable by said shaft to release said energy in adjustably timed relation to the operation of said storing means, and means to operatively apply said energy to said table.

8. In a machine tool in combinat'on, a work supporting table, means to apply to and withdraw from said table a predetermined force to cause a pulsation thereof, manually operable means to vary said predetermined force, and manually operable means to vary the amplitude of said pulsation. y

9. In a machine tool in combination, a work supporting table, means to apply to and with- -draw from said table a predetermined force to cause a pulsation thereof, manually operable means to vary said predetermined force, and manually operable 4means independent of said first manually operable means, to vary the amplitude of said pulsation.

10. In a machine tool in combination, a work supporting table, means to apply to and withl draw fromvsaid table a predetermined force to cause a pulsation thereof, manually operable means to vary said predetermined force, and manually operable means, including a micrometer screw, to vary the amplitude of said pulsation.

11. In a machine -tool in'combination, a work supporting table, means to apply to and withdraw from said table a. predetermined forcetc cause a pulsation thereof, manually operable means to vary said predetermined force, manually operable means independent of said first manually operable means, to vary the amplitude of said pulsation, and'manually' operable means to adjust the position of said table.

12. In a machinetool in combination, a work supporting table, means including a toggle to apply to and withdraw from said table a prede-` termined force to cause a pulsation thereof, mani ually operable means to vary said predetermined force, andv manually' operable means to vary the amplitude of said pulsation. l

13. In a work supporting and clamping device, in combination, a base, a table slidably guided thereby, Wedging means adapted to move said table, second wedging means adapted to actuate said'rst wedging means, a toggle operatively attached to said second wedging means, and power means to actuate said toggle.

14. In a work supporting and clamping device, in combination, a base, a table slidably guided thereby, wedging means adapted to move said table, second wedging means adapted to actuate said first wedging means, a toggle operatively attached to said second wedging means, and power means to actuate said toggle through a predetermined amplitude.

15. In a work supporting andvclamping device, in combination, a base, a table slidably guided thereby, wedging means adapted to move said table, second wedging means adapted to actuate said rst wedging means, a toggle operatively atmeans to actuate said toggle through a predetermined amplitude and means to vary said predetermined amplitude.

16. In a work supporting and clamping device, in combination, a base, a table slidably guided thereby, wedging means adapted to move said table, second wedging means adapted to actuate said first wedging means, a toggle operatively attached to said second wedging means, and power means to actuate said toggle through a predetermined amplitude with a predetermined force.

17. In a work supporting and clamping device, in combination, a base, a table slidably guided lthereby, wedging means adapted to move said table, second wedging means adapted to actu-- ate said iirst wedging means, a toggle operatively attached to said second wedging means, power means to actuate said toggle through a predetermined amplitude with a predetermined force, manual means to vary said predetermined force and manual means to vary said amplitude.

A18. In a work supporting and clamping device in combination, a base, guide rails thereon, a table, guide shoes attached to saidy table, and

slidably engaging said rails and Wedging means 'to pulsate said table, said shoes being adjustable to take up wear between said shoes and said rails.

19. In a machine tool in combination a power shaft, a work supporting table, and means to pulsate said table comprising means operable by said shaft to store energy, tripping means operable by said shaft to release said energy in timed relation to the operation of said storing means, and means to operatively apply said energy to said table.

20. In a work supporting and clamping device, in combination, a base, a table slidably guided thereby, wedging means adapted to move said table, a second wedging means adapted to actuate said first wedging means, a toggle operatively attached to said second wedging means, power' CHARLES H. iIoWLAND-srmARMAN. 

